This proposal, submitted in conjunction with the MSI-FLASH network (Menopausal Symptoms Initiative- Finding Lasing Answers to Sweats and Hot Flashes), will compare the efficacy of two different doses of exercise against usual care (menopause education) for alleviating vasomotor symptoms. Both exercise arms will have a target exercise expenditure of 16 kcal/ kg/ wk, with the lower dose group performing at 50- 55% of predicted maximum heart rate (HRmax), and the higher dose group performing at 65-70% HRmax. The participants in the exercise trial will be drawn from 4 of the field sites participating in MSI-FLASH: Kaiser Permanente Northern California, Group Health in Seattle, University of Pennsylvania, and University of Indiana. The participants in the two exercise groups will meet once in-person with an exercise counselor at the start of the intervention and then by phone every week for the first two months and every other week for the last two months. The counseling will emphasize behavioral change strategies consistent with social cognitive theory, such as the setting of intermediate small-step goals, as well as practical knowledge and skills necessary for safe and effective exercise training. The control group will receive written health education material and counseling monthly by telephone. The recruitment period will extend over nine months, during which 450 women, who meet eligibility criteria, will be randomly assigned, in approximately equal numbers to each arm, using a design blocked on site, race/ethnicity and menopausal status. Because of the nature of the intervention, treatment assignments will not be blinded. Frequency of VMS, measured both subjectively and objectively will be assessed at the beginning, mid-point, and end of the intervention. Other shared network outcomes, including bother, severity, and interference of VMS, mood, sleep, and quality of life, will also be assessed before and after the intervention, as will important protocol-specific variables, such as physical activity, physical fitness, and body size. The overall goal of MSI-FLASH is to accelerate the identification of effective remedies to relieve vasomotor symptoms, the main objective of RFA-AG-08-004, by creating a network of scientists who are highly knowledgeable about the menopausal transition and experienced in the conduct of women's health trials. The MSI-FLASH Data Coordinating Center (DCC) will be jointly led by Andrea LaCroix and Garnet Anderson who have served together as Co-Prinicpal Investigators of the Women's Health Initiative, Clinical Coordinating Center (Seattle) for more than a decade. The five clinical field sites participating in the MSI-FLASH network are located in Boston (Drs. Lee Cohen and Hadine Joffe, PIs),Indianapolis, IN (Dr. Janet Carpenter, PI),Oakland, CA (Drs. Barbara Sternfeld and Bette Caan, PIs), Philadelphia, PN (Dr. Ellen Freeman, PI) and Seattle, WA (Drs. Katherine Newton and Susan Reed, PIs). This multidisciplinary investigator group is proposing five randomized controlled trials testing a range of behavioral, mind-body, hormonal and pharmacologic interventions.